fix: the git commit hash in the docker is empty string

[nic-chen]

Please answer these questions before submitting a pull request

• Why submit this pull request?

• Bugfix

• New feature provided

• Improve performance

• Backport patches

• Related issues
  close Bug: the commit_hash in the demo is empty string #1438

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Bugfix

• Description
  In the docker build, the compressed package of github is directly downloaded, which does not contain git information, that causes the git commit hash to be empty string

• How to fix?
  use git repo source code to build docker image.

[codecov-io]

Codecov Report

Merging #1446 (5b65877) into master (8796fa1) will increase coverage by 0.09%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1446      +/-   ##
==========================================
+ Coverage   67.61%   67.71%   +0.09%     
==========================================
  Files          48       48              
  Lines        3042     3042              
==========================================
+ Hits         2057     2060       +3     
+ Misses        741      738       -3     
  Partials      244      244              

Impacted Files	Coverage Δ
api/internal/core/storage/etcd.go	46.36% <0.00%> (+2.72%)	⬆️

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[imjoey]

/lgtm

Thanks.

[imjoey]

Hi. @juzhiyuan @starsz , this PR needs to be backported to v2.4 branch for release 2.4.